Processes of producing ether alcohols



Patented June 11, 1946 UNITED sT 'r'Es' PATEN or'rnonucmo. arm ALCOH 'rnooass'as O ICE Philip I. Bowman: mast, N. Y., and Robert H.

Barth, Ridgewood, and Harry by memo assignments, Hey- N. 1., assiznors,

Burreli, laramua,

den Chemical Corporation, New York, N. Y., a

corporation of No Drawing. Application 1, 1943, Serial No. 414,328

1 6 Claims.

This invention relates to a process of producin: ether alcohols by the reaction of alkene oxides and pentaerythritol, polypentaerythritols and mixtures of such polyhydric alcohols. More specifically, the invention relates to new-catalysts for such reactions and new reaction products which result irom the use thereof.

The reaction between pentaerythritol and ethylene oxide is described in Patent No. 1,922,-

459. The catalysts disclosed in said patent are boric anhydride and ,boric acid. The present in-- vention relates to new reaction products formed by the catalytic action of other catalysts which give a different type of product than do boric acid and boric anhydride. This feature is one of the main novel features of theinvention. Another novel ieature of the invention is the formation of new ether alcohols irom dipentaerythritol and from pleopentaerythritol. A further feature of the invention is the formation of new ether ester alcohols from partial esters of pentaerythritol, ,dipentaerythritol, and pleopentaerithritol, the preparation of which is described in copending application Serial No. 447,782, filed June 20, 1942.

In the manufacture of pentaerythritol bythe condensation of acetaldehyde and formaldehyde, in addition to pentaerythritol itself, smaller amounts of hydroxylated substances are also obtained. One of these substances, which is .obtained in a considerable amount, is dipentaerythritol, which is an ether having the following structure: 7

CHQOH onion HOHaC-Jl-CHr-O-CHr--CHrOH term is meant those compoundshaving higher 7 g 2 tol, together with some 'pentaerythritol and a minor amount of other compounds which, according to the best evidence available, includes other related alcohols. .11; is the residue remaining after the separation of the major amount of pentaerythritol and 'dipentaerythritol from the reaction product resulting from the condensation of formaldehyde and acetaldehyde in the presence of an alkali.

Dipentaerythritol, tripentaerythritol and pleopentaerythritol may be grouped together under the generic term polypentaerythritols, by which molecular weights than pentaerythritol which are formed either actually or theoretically by etheritying one or more of the hydroxyl groups of,

pentaerythritol with other pentaerythritol residues;

One of the objects of this invention is to prepare a new series of reaction products bythe reaction of alkene oxides and polypentaerythritols; These new products are of interest as interme diates in the chemical, pharmaceutical, plastic, and varnish industries.

A still further object of the invention is to prepare from pentaerythritol or polypentaerythritols or their partially esterified reaction products, new hydroxy ethers by reaction with alkene oxides. These hydroxy ethers may be further esterifled,

if desired, and may be used as plasticizers or f Such products are more fully de scribed in the examples hereinafter.

A further object of the invention is to provide new catalysts for the reaction of alkene oxides with pentaerythritol or 'polypentaerythritols. Th term catalyst in this specification is applied to an agent, added in small amounts, which directs the course and influences the speed of the reaction, and which may or may not come out of the reaction unchanged. Boric acid and boric anhydride. which have been heretofore disclosed in Patent No. 1,922,459, are not true catalysts; in fact they inhibit the reaction of alkene oxides with pentaerythritol compounds, as is shown in Example 2 hereinafter.

Catalysts for use in the process of our invention and which decrease the time of reaction,

lower the temperature at which the reaction occurs, and increase the amount of alkene oxides which reacts are the following: acetic acid and 3 Y t higher fatty acids, acetic anhydride and higher fatty acid anhydrides, acetyl chloride, and higher pound so that in the end there is probably present a small amount of a hydroxy fatty acid ester of pentaery'thritol, or dipentaerythritol, or other polypentaerythritol. This reacts rapidly with the alkene oxide. The ester groups are exchanged by the alkene oxide, and being free. can activate dipentaerythritol and iii '10 their acid group, with the pentaerythritol com- 4 inafter. was mixed'with the specified alkene oxide in a steel autoclave (which was externally heated. thetemperature being controlled electrically) in the' specified ratioof definite molecular equivalents of alkene oxide to hydroxyl groups. For

example, one molecular proportion of penetaerythritol, which has four hydroxyl groups, was reacted with four molecular proportions of ethylene 1 oxide to give the first product listed in Table I hereinafter. .The time required for the reactions varied from about two hours at 175 C. to eight hours at 150 C., but each reaction mixture was heated for hours at the specified temperature. Boric acid was used as the catalyst in an amount equal to 0.10 to 0.15 per cent of the total weight of reactants. The products which were obtained and their characteristics are described in Table I.

TABLE I Reaction products obtained with boric acid catalyst Mols oi n drc 1 an: no used 11 3a fi l i'i Deacriptionoiproduct com on eneo e o e Starting 1 7 9 per on store mommy group 0. I ryth ritol Eth 'lene oxide. 1 21 4 Liquid viscous pale ow B. P. 250-280" C. at 2 mm. Xe 2 l4. 0 Liquid: less viscous t an above, pale yellow. Technical ntaerythritol ..do 1 20.9 Liquid viscous, 0 allow. Technical pentaerythritol -.do 1 22-0 Very us, e e owliquid. Do db 2 14.9 Less viscous ove, a yellow liquid. Pleopentae britol o 1 215) Heavy paste, having gelestruoture. Dipentaeryt itol..-- Propylene oxide. 0. 84 18. 0 Va viscous, cloudy liquid.

Do p l Dar brown, very viscous liquid. Pentaerythritol Ethylene oxide-- 0.5 V Viscous pale yellow liquid, cloudy.

ulated so as not to over shoo the desired temperature. Good mixing is essential. Pressures and temperatures should be controlled.

Alkene oxides which may be used include ethylene oxide. propylen oxide, and epichlorohydrin.

The reactions require anywhere from 2 to hours at temperatures ranging from 110 0. (using the acetate type of catalyst) to 175 C. (using boric acid or no catalyst). The reaction is judged to be complete when the pressure drops nearly to atmospheric.

The following examples and comparative examples illustrate the invention:

Comparative Example 1.Pentaerythritol or a polypentaerythritol, as specified in Table I here'- Some of'the productsbbtained as described in Comparative Example 1 were reacted with 40 acetic and propionic anhydrides and mixtures of anhydrides, and others were esterified with fatty acids themselves. as described in copending application Serial No. 378,052, filed February 8, 1941 (Patent No. 2,356,745), and in ways known to those skilled in the art. The resulting new compounds varied from viscous oils to colorless oily liquids which. were compatible with nitrocellulose, cellulose acetate and vinyl chloride acetate.

Example 1.A partial ester of pentaerythritoli or a polypentaerythritol as specified in Table II hereinafter was heated with the specified alkene oxide as described in Comparative Example-1 at a temperature between 150 C. and 175 C.

in a steel autoclave for the specified period. Onemol of alkene oxide per free hydroxyl group was added in each case. although, as indicated in Comparative Example 1, more mols of alkene oxide could have been used to give a higher molecular weight product. In these reactions no additional catalyst was used, since the partial ester serves as its own catalyst.

" Turn It a Time of Stem partial ester Alkene oxide g hating, Nature 0! product 7 6 c I Dipen e iml monomyristatc Ethylene oxide.. 175 24 Viscous oil. Pen to] monostearate-.- --.--d.o- 176 10 .Boft wax.

ipentaerythritol triacetatc do- 176 10 Viscous liquid. Technical pentaerythrltol monogtearate .do. I 10 Soft wax. Penteerythrltol monocapraie'. --d.o...-- l0 Viscous oil. Dipentaerythritolmono soy beau fatty acid ester n 175 10 Example 2.-The eilect of various catalysts on the reaction or dipentaerythritol and ethylene oxide was studied, using the following general procedure.

One molecular proportion of dipentaerythritol was mixed with 30 molecular proportions of ethylene oxide together with the specific quantity of catalyst in a steel autoclave, and the mixture was heatedto 175 0. The time required to reach 175 0. was approximately hours, and an additween 246 0. and 255 0., 13.3 cent between 256 0. and 265 0., per cent between 266 0. and 275 0., 13.3 ,per cent between 276 0. and 285 0., 13.3 per cent between 286 C. and 308 0., and 13 per cent residue (above 300 0.) at a pressure of 3 mm. of mercury. Hydroxyl values and refractive index measurements on fractions of each distillation together with the boiling points, as given in Tables IV and V, indicate tional 8 hours were allowed, to complete the reaction. The quantity of catalyst which was added was 0.13 oi thetotal weight. of reactants. The product was boiled to remove the excess ethylene oxide, and the residue weighed. The hydroxyl value was also determined as a check on the amount of ethylene oxide reacted. From the analytical data, the mols of ethylene oxide per hydroxyl group which reacted were calculated,

It is evident from the table that the use of the acetate radical as a catalyst, whether added as the free acid, anhydride, or ester, promotes the reaction of a large n'umber of mols oi ethylene oxide; and that the use of boric acid, etc., results in limited-reaction even in the presence of a large molecular-excess of ethylene oxide. The amount of ethylene oxide which actuallyreacted when boric acid is used as a catalyst is even less than the amount which reacted without any catalyst whatsoever.

Example 3.This example serves to show the diflerences in the reaction products which result when two difierent catalysts are used, namely (1) boric acid and (2) pentaerythritol tetraacetate.

A mixture of 544 parts (approximately 4 molecular parts) of pure pentaerythritol (melting point 260-262 0.) and 704 parts (approximately 16 molecular parts) of ethylene oxide were heated in two separate experiments with 1.7 parts of boric acid ahd 1.7 parts of pentaerythritol tetraacetate, respectively. Both reactions were complete. The one using boric' acid required 17 hours at 125 C. and 4 hours at 150 0. to complete. The one using the pentaerythritol tetraacetate required 16 hours at 110 0. to complete, as indicated by a-pressure drop to atmospheric. The reaction products in each case were subjected to vacuum distillation.

In the case of the boric acid catalyzed reaction mixture, 60 per cent distilled between 250 0. and 260 0.. 20 per cent between 260 C. and 280 0., and 20 per cent between 280 0. and 290 0., at a pressure oi 2 mm. of mercury.,, In the case of the pentaerythritol tetraacetate catalvzed reaction product, 23.3 per cent distilled between 234 0. and 245 0., 13.3 per cent bethat while both products are mixtures, they are mixtures of diil'erent compounds whose .con-

stitutions have not as yet been determined.

' TABLI IV Distillation of pentaerythritol-ethylene oxide reaction product-Boric acid catalyst- ,7 Bo Percent oi Faction In s tom Percent Refractive at 2 mm. weight on 1.. 250-0 00 24. 7 1. 481 a... coo-rec so no. 2 1. 480 3... 280-290 20 10.9 1. 479 a Residu 1 Very little Tun V Distillation of pentaerythritol-ethylene oxide reaction prodwct-Pentaemthritol tetraacetate' catalyst Bo Percent oi Fraction a mm Percent Refractive at 8 mm. weight on 234-245 23. 3 28. 8 1. 479 240-255 13. 3 24. 8 1. 482 256-265 13. 3 2i. 8 1. 481 266-275 10. 0 20. 2 1. 480 276-285 13. 3 18. 9 l. 478 280-306, 13.3 10.1- 1.478 Over 306 13. 0 13. l

Reference is made to our copending application Serial No. 545,888, filed July 20, 194.4, which claims subject matter originally disclosed but not claimed herein. I

Having. thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A process or preparing an ether alcohol which consists in'heating together under pressure an excess oil an alkene oxide with an alcohol.

selected from the group consisting of pentaerythritol and polypentaerythritols in the presence of a catalyst selected from the group consisting of carboxylic acids, their anhydrides, their chlorides, and partial and complete esters or carboxyllc acids and polyhydric alcohols.

2. A process of preparing an ether alcohol which consists in heating together under pressure an excess 01' an alkene oxide with an alcohol' selected from the group consisting of pentaerythritol anl polpentaerythritols in the 5. A process of preparing an ether alcohol which consists in heatin together under pres-- sure an excess of an nlkene oxide with a. polypenteerythritol in the presence 01 a. catalyst selected from the gx'oup consisting of carboxylic acids, their anhydrides, their chlorides, and partie! and complete esters of 'csrhoxyiic acids and poiyhydric alcohols.

6 dride.

8. A process 01 preparing an ether aicohoi which consists in heating together under pressure an excess of an aikene oxide with a poly pentaerythritol in the presence of acetic enhy- Pnms v1. mm. ROBERT n. m. 

